Sleep disturbance is the most common symptom among Veterans with posttraumatic stress disorder (PTSD), with prevalence rates of over 90% for insomnia and around 70% for obstructive sleep apnea (OSA). Beyond symptom-driven distress, PTSD, OSA, and insomnia are problematic because of their effects on physical health, functional outcomes, and quality of life. While there are effective treatments available for OSA and insomnia, current treatments for these disorders have not been adapted to the needs of the large number of Veterans experiencing PTSD. This adaptation is necessary to target the problems that are particularly detrimental to this group of Veterans. For example, patients with PTSD have lower positive airway pressure therapy (PAP) adherence than those without PTSD, which is significant because increased adherence to PAP is associated not only with reduced nightmares but also with improved PTSD symptoms overall. In addition, though behavioral treatments for insomnia have been studied in those with PTSD with promising results, little is known about how to address comorbid OSA and insomnia because patients with OSA are typically excluded from insomnia trials in spite of high levels of comorbidity. Moreover, insomnia itself is associated with decreased PAP adherence. Currently, there is no integrated approach to treating Veterans with these comorbidities concurrently, and existing treatment is often not coordinated between different treatment clinics and consequently may be more prolonged than needed. The proposed project allows for the evaluation of a treatment that addresses OSA and insomnia in tandem and within the context of PTSD, which can serve to consolidate treatment for Veterans with these issues. The proposed CDA-2 consists of a pilot randomized controlled trial evaluating the efficacy, feasibility, and acceptability of Apnea and Insomnia Relief (AIR), a behavioral intervention that combines elements of psychoeducation, motivational interviewing, cognitive behavioral therapy for insomnia, and PAP desensitization. The trial will compare AIR (n = 40) with sleep education (control condition; n = 40) among Veterans with OSA, insomnia, and PTSD. Treatment will be administered partially in person (sessions 1-2) and partially via telehealth (sessions 3-6) to enhance Veteran engagement and broaden access to care. Functional outcomes will be quality of life (primary outcome) and sleep-related functioning at post-treatment and three- month follow-up (Aim 1). We will also measure change in insomnia and PTSD symptoms as well as PAP adherence. Insomnia symptoms will be assessed using subjective and objective sleep measurement. Aim 2 will consist of a multifaceted assessment of the acceptability and feasibility of AIR. Veterans will complete self- report questionnaires and a follow-up interview to assess satisfaction with treatment, both in terms of content and method of delivery (i.e., in-person and telehealth). We will also measure treatment dropout and attendance at the first PAP follow-up appointment to evaluate engagement in care. Finally, we will conduct an exploratory analysis of moderators of treatment outcome (Aim 3), such as baseline sleep apnea severity or concurrent medication use, to facilitate adjustments to the protocol or identify subpopulations for whom an alternative treatment may be recommended. The proposed project could be highly impactful for the increasing number of Veterans with PTSD and sleep disturbance, as well as their providers who lack clear guidelines for how to provide behavioral treatment for sleep disorders in patients with PTSD. Moreover, by treating these disorders concurrently, there may be an improvement in Veterans? functioning and a reduction in service utilization. This intervention is consistent with the VHA mission of providing exceptional healthcare. Additionally, the proposed intervention is in alignment with the VHA vision of providing patient centered and evidence based care delivered by engaged and collaborative teams in an integrated environment.